Air heater



Sept. 26, 1933.

Filed May 15, 1931 A. SOLOOS AIR HEATER 2 Sheets-Sheet l Fi gl. e0

Fig.2 J I E W1 4 WI I4 "I M L l N I J V 3 i r 32 mm Sept. 26, 1933.

A. soLoos 1,927,959

AIR'HEATER Filed May 15, 1931 2 Sheets-Sheet gmmk w FYI Sc/cos "7338'g-9 as? Patented Sept. 26 1933 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to devices for heating air for the purpose ofheating dwelling and other buildings, and vehicles, and has specialreference to-heating by means of an electric current.

The objects of my invention are, first, to provide an air heater of highefficiency whereby the heat developed by the electricity is very rapidlyconducted away. from the heated wire and is spread over a large area ofmetal in contact with the air to be heated; second, to provide a devicewhich will carry the heat away from the heated wire so rapidly as toprevent the heated wire from reaching a temperature at which it willglow; third, to form the structure in such a manner that the several airheating surfaces will coact to form free air ducts surrounding theheating wire, to heat the air therein and cause it to circulatetherefrom; fourth, to form the structure by bending a series of platesand by confining the heating wire in the points of contact of saidplates; fifth, to form the structure by clamping the series of bentplates within a frame; sixth, to form the structure in such manner thatit may be tilted to direct the flow of air therefrom; seventh, to formthe heating element of one or -more continuous wires, threaded throughsuitable cylindrical insulators, and supporting said heating elements inzig-zag rectangular manner between the contacting bends of the heat con=ducting plates; and eighth, to provide air heater which is cheap tomake, highly efficient, well insulated, and safe.

I attain these and other objects by the devices,

36 and arrangements illustrated in the accompanying drawings, in which--Fig. 1 is a plan view of the top of my improved electric air heater;Fig. 2 is a side elevation there of; Fig. 3 is an end elevation thereof;e is a m horizontal section of a portion of the electric air heater;Fig. 5 is a side elevation of the portion shown in Fig. 4, and brokenapart at the center to reduce its length in the drawings; Figs. 6 and lare and and side views, respectively, of the metal as sheath and hood ofthe heating element at the 5 standards 1, by means of a pair oftrunnions 2,

mounted in the bearings 3 ,on the upper ends of the said standards 1.

The frame of my improved air heater comprises two end frames 4, carryingthe trunnions 2, and the four horizontal corner members 5 suitablysecured to the said end frames 4. The end frames 4 may be made from asingle plate, and may have flanges extending around their edges by whichthe said corner members 5 may be attached thereto. The frame thusformed, forms a rectangular open body within which the air heatingplates are supported and clamped.

The heating element shown in the drawings comprises a pair of parallelresistance wires 6 and "7, threaded through the two, holes in thecylindrical insulators 8. It is, of course, undenstood that the numberof such wires is not confined to two, as illustrated, but maybe a singlewire or any number of such wires "as may he desired or convenient. Theseinsulators 8 are made of porcelain or other suitable material and are ofuniform diameter, being in practice about one-quarter inch in diameter,and of uniform lengths, about three inches is found to be a con venientlength. The insulators are strung loosely on the two wires 6 and l andthe whole length is then strung continuously through the heater, asbelow described. The resistance wires illustrated are made oi nichrome,preferably oi number twenty-two guage.

The course which this length of heating eleznent follows may hedescribed as follows; starting at one end, first it passes horizontallyfrom the terminals Q and ill at one end, on the under side of theheater, a distance oi one insulator length (3 inches) to the first pointwhere the heremaiter described plates contact; then it turns upward, atright angles within the tube formed of such plates, as hereinafterdescribed, and forms a vertical heating length for a distance of threesuch insulator lengths (9 inches) then it turns horizontally on top ofthe heater, a distance of one insulator length to the second such tube;then it turns downward at right angles within the second tube a distanceof three such insulator lengths to the under side or the heater; then itagain turns horizontally to run on the underside of the heater 9.distance of one insulator length to the third such tube; and so on, upand down for a series of four such vertical lengths; then it also turnsthrough a. horizontal angle of about forty-five degrees and passes alongthe under side of one ofthe dlag onals to the second row of such tubesand passes similar y up and down for a series of live such verticalheating lengths; then it again passes along the upper edge of one of thediagonals to the third row of tubes and passes similarly down and up fora series of four such vertical heating lengths; and it passes along theupper edge of a diagonal to the fourth row of vertical heating lengthsand passes down and up the tubes five times; and thence it passes'by ashort horizontal length along the under side of the heater to the end.Both the wires'fi and '1 are secured separately to the terminals 9 and10, respectively, at each end.

As shown in Fig. 8, when the voltage of the energizing circuit isrelatively high, the two wires 6 and 7 are arranged in series bysecuring the terminals 9 and 10, at one end, together (Fig. 4) by aconnecting wire 11, and by connecting them separately at the other endto the two wires of the energizing circuit. In Fig. 9, I have shown theconnections for a lower voltage circuit, in which the wires 6 and 7 areconnected together in parallel, in the usual manner. Thus it will beseen that the heating wires 6 and 7 travel together in parallel linesback and forth, up and down, throughout the heater and that they,therefore, uniformly distribute their heat throughout the entire area ofthe heater, and that they uniformly heat all the air volume con tainedin the spaces of the heater and thus unliormly affect a very largevolume of air and cause a strong circulation of the air from the heater.

The heat developed by the said heating circuit is conducted awaytherefrom by the following described air-heating plates. Two sets ofsuch plates are used in the construction 01' my improved heater. First,a set of four central plates 12 are provided. Each of these plates 12extend from end to end of the heater frame and each is provided withstraight semicircular grooves or troughs 13 extending from top to bottomand adapted to receive the vertical heating lengths of the heatingelement, as above described. Two of these plates 12 have four suchtroughs 13 and two have five such troughs 13.

The horizontal members of the heating circuit insulators 8 are securedto the said plates 12, between each trough 13, by means of fasteningplates 14 which are riveted or otherwise secured to the upper or loweredges of the plates 12, and. which loop over and aroimd the saidhorizontal. insulators t. The ends of these fastening plates l-i areextended laterally to form hoods it": which I extend over and protectthe portion of thcswires 6 and 7 as they pass from the vertical to thehorizontal portions of the heating circuit.

The other set of heating plates is composed of five plates 16. Theseplates 16 also extend from end to end of the heater and each is bent toprovide a series of semicircular bends or troughs 17, extending from topto bottom, similarly to the troughs 13 in the plates 12. The first saidplate has four such bends 17, all made in the same side of the plate;the second, third and fourth plates each have nine such bends 11', madeaitemately in opposite sides of said-plates; and the fifth plate hasfive such bends made in the same side of said plate. As seen in Fig. 4,these semicircular bends 17 to oneplate 16 are complementary to thetroughs 13 of the plate 12 to complete the cylindrical casing or tubefor the vertical heating circuit insulators, while the bends 1'! of thenext plate 16 lie outside of the said troughs 13 of the plate 12, andare supplementary to the said troughs.

The plates 16 are also bent on a sharp angle at each side of theabove-described semicircular bends 17, to form diagonals so that eachsaid plate 16 zigzags back and forth from one row of vertical heatingelements to the adjacent row of heating elements and back again from endto end of the heater.

The structure thus formed is held together by means of the horizontalcorner members 5 of the supporting frame. The resulting form of theheater comprises, therefore, six radiating fins extending from eachvertical tube in which a heating unit is positioned and these six fins,cooperating with fins from the surrounding vertical tubes, enclose sixcolumns of air. Each small column of air is therefore surrounded bythree heated plates with the result that the area of exposed heatedsurface of the fins or plates is quite large in comparison with thevolume of air enclosed thereby and that the air is instantly andcontinuously heated and the fins are correspondingly cooled. The fins orplates are heated primarily by the portions of the heating circuit inthe vertical tubes, but the plates 12 are heated, in addition, by thehorizontal members contained in the fastening plates 14.

Thus it will be seen that I have produced an electric heater which is ofextreme simplicity to manufacture and which will be of very highemciency.

Having, therefore described my invention, what I claim and desire tosecure by Letters Patent. is:--

1. An air heater comprising a tube composed oi two plates, each bentcomplementary to each other to together form said tube, and eachextending from said tube in diverging planes; a third plate bent tosupplement the outside of one of said complementary parts and extendingtherefrom in planes diverging from the adjacent portions of the plates:and a heating element contained in said tube.

2. An air heater comprising two parallel noncoaxial tubes composed oftwo plates bent complementary to each other at spaced intervals totogether form both said tubes, each plate extending from each tube indiverging planes to form heat distributing fins; and a heating elementcontained in each said tube.

3. An air heater comprising two parallel tubes composed of two platesbent complementary to each other, at spaced intervals, to together formsaid two tubes, the spaced interval of one such plate being shorter thanthe spaced interval of the other such plate, the first said plateextending directly from one tube to the other, the secend said platediverging from and converging towards the first plate in the intervalbetween said tubes, thereby forming separated heat distributing fins;and a heating element contained in each such tube.

4. An air heater comprising three parallel tubes positioned at theangles of a triangle and composed of three plates, one of said platesbent to form one-half of two of said tubes, 9. second said plate bent toform one-half of the third tube, and the third said plate bent to formthe complementary halves of all three tubes, the first and second platesbeing parallel and the third plate lying between the first and secondplates and being bent at the tubes to pass consecutively from one tubeto the other, said third plate lying in divorcin planes with respect tothe first and secend plates, thereby forming a heat distributingtriangle having a tube at each angle; and a heating element containedineach such tube.

5; An air heater comprising a plurality of parallel tubes arranged instaggered rows and formed of a plurality of plates, each plate havingspaced semicircular bends, one such plate extending in straight coursefrom tube to tube in each row, the other such plates lying between eachpair of said straight plates and passing in zigzag manner from the firsttube in one row to the staggered first tube in the next row andreturningto the second tube in the first row, and so forth, thesemicircular bends on any straight plate lying in the same side, and thesemicircular bends in the diagonal plates lying in alternate sides andbeing alternately complementary and supplementary to the bends in thestraight plates; and a heating element contained in each said tube.

6. An air-heater comprising a pair of end rectangular frames; cornerbars jointing corresponding corners of said end frames; a series of bentplates each extending in zigzag manner from end to end of the heater andcontacting at their bends to form a honeycomb compressed between saidcorner bars; and a heating element at each point of contact 01' saidplates whereby all said separated diverging plates are heated.

7. An air heater comprising a pair of standards; a pair of end frames;corner bars'joining corresponding comers of said endframes; trunnionsjoining said end frames to said standards, whereby the air heater may betipped to any desired angle; a series of bent plates each extending inzigzag manner from end to end of the heater and contacting at theirbends to form a honeycomb compressed between said comer bars; and aheating element at each point of contact of said'plates, whereby allsaid separated diverging plates are heated.

8. An air heater comprising a pair of end rectangular frames; cornerbars joining corresponding corners of said end frames; a series of bentplates each extending in zigzag manner from end to end of the heater; aseries of straight plates interposed between said zigzag plates; tubesformed at the points oi contact of said zigzag plates with said straightplates; and a heating element contained in each said tube.

- ALF SOLOOS.

